1. Field of the Invention
The invention relates to a sensor. More particularly, the invention relates to a light sensor.
2. Description of Related Art
In recent years, sensing devices have been playing important roles in most industrial applications and automated control uses. Sensing devices usually include temperature sensors, humidity sensors, pressure sensors, magnetic sensors, illumination sensors, distance sensors, light sensors, and the like. Among these, light sensors have been extensively applied in various consumer products with the popularization of liquid crystal display panels and various mobile devices (such as mobile phones, personal digital assistants (PDAs), global positioning systems (GPSs), notebooks, netbooks, and so on).
Generally, light sensors contain pixels arranged in a matrix. In particular, increasing pixel density leads to shorter distance between pixels. As a result, the distance between two lower electrodes of two adjacent pixels is decreased, thus readily causing leakage current between the pixels when a voltage difference exists between the lower electrodes. If the distance between adjacent lower electrodes is increased, then the electric field in the middle region of the pixels becomes too weak. As a result, the photoelectron produced cannot readily reach the lower electrodes, thus generating a lag phenomenon. Moreover, light can also readily enter between pixels and cause crosstalk phenomenon between the pixels.